Switch



Feb-.122, 1938. L. E. FISHER ET AL 2,108,812

SWITCH Filed Jan. 13, 1936 ATTORNEY.

Patented Feb. 22, 1938 PATENT GFFICE SWITCH Lawrence E. Fisher and William Il. Frank, Detroit, Mich.

Application January 13, 193s, serial No. 58,870

5 Claims.

This application discloses a novel circuit protective switch shown in the appended drawing whose- Fig. 1 is a side view;

Fig. 2 is a section view on line 2 2, Fig. 1; and 1.whose i Fig. 3 is an end view.

In Figs. 1-3 there is disclosed a switch wherein stationary contacts 54 are adapted to be connected through movable contacts 55 engaged by springs 56, and a U-shaped bimetallic thermal element 51 on the outside ofthe movable housing 58 and mounted thereon by means of pins 59 which also mount the movable contacts 55 and electrically connect these to the ends of the U- shaped thermal element 51. 'Ihe bight 8l of the thermal element is bent to form a lug which is normally positioned under a catch 52 formed on an insulation block 63 secured to the base 54 in an appropriate manner. The slide 65 of the block 58 between the stationary contacts 5I is continued to form an extension 66 which passes through a slot 51 of the base 64 to be engaged by a coiled compression spring 58 housed in a base portion 88.

The operation of the parts is as follows: When the switch is in ON position, as on normal load, the thermal element has its lug 6| caught under the catch 62 and the housing 58 is held down in the position illustrated andthe circuit is established from one contact 5l through a movable contact 55, apin 59, and the U-shaped element 51 back through a second pin 58, a second contact 55, to the second stationary contact 54. When an overload arises, the thermal element warps to the left, Fig. 1, so that its lug is free of the catch 62, whereupon the spring 58 under stress expands and causes the block 58 to move up so that its contacts 55 leave the stationary contacts 54 and open the circuit, movement of the block being arrested by the engagement of the lower end of the slide against the under surface of the base 64.

We claim:

1. A circuit interrupter comprising a pair of stationary contacts, a movable insulation block having cells closely tting around and constantly closed by said stationary contacts in all positions of the block, a `contact forming a wall portion of each cell and carried by the block and movable therewith to engage or be free of a stationary contact in the corresponding cell, the block contacts being electrically connected by movable circuit current responsive means whereby the block contacts and such means bridge the stationary contacts, the circuit current responsive means comprising the movable part of a release latch which normally holds the block in closed circuit position, and means constantly tending to move the block to open circuit position and inhibited by the latch.

2. A circuit interrupter comprising a pair of stationary contacts, a movable insulation block having cells closely fitting around and constantly closed by said stationary contacts in all positions of the block, a. contact forming a wall portion of each cell and carried by the block and movable therewith to engage or be free of a stationary contact in the corresponding cell, the block contacts being electrically connected, whereby they bridge the stationary contacts, the connection including a circuit current responsive release means operating on a circuit abnormality to move the block to open circuit position.

3. A circuit interrupter comprising a pair of stationary contacts, a movable insulation block having cells closely iitting around and constantly closed by said stationary contacts in all positions of the block, a` contact forming a wall portion of each cell and carried by the block and movable therewith to engage or be free of a stationary contact in the corresponding cell, the block contacts being electrically connected, whereby they bridge the stationary contacts, the connection including a movable circuit current responsive release latch which normally holds the block in closed circuit position, and means constantly tending to move the block into open circuit position and inhibited by the latch.

4. A circuit interrupter comprising a pair of stationary contacts, a movable insulation block having cells closely fitting around and constantly closed by said stationary contacts in all positions of the block, a contact forming a Wall portion of each cell and carried by the block and movable therewith to engage or be free of a stationary contact in the corresponding cell, the block contacts being electrically connected by circuit current responsive means whereby the block contacts and the means bridge the stationary contacts, the means also serving to control the position of the block with respect to the stationary contacts and thus controlling the flow of current through the interrupter.

5. A circuit interrupter comprising a pair of stationary contacts, a movable insulation block having cells closely tting around and constantly closed by said stationary contacts in all positions of the block, a contact forming a wall portion of each cell and carried by the blo'ck and movable therewith to engage or be free of a stationary contact in the corresponding cell, the block contacts being electrically connected by circuit current responsive latching means whereby the block contacts and the means bridge the stationary contacts, the latch normally holding the block in circuit closing position, but operating, on overload, to permit the block to be moved away from circuit closing position automatically.

I LAWRENCE E. HSI-1ER. 

